Variant Type of Posterior Reversible Encephalopathy Syndrome Associated with Deep Brain Hemorrhage: Case Report and Review of the Literature

Abstract

Various radiologic patterns of posterior reversible encephalopathy syndrome (PRES) have been reported. Among them, PRES involving brainstem, thalamus, or deep white matter and lacking parieto-occipital edema is rare. Although PRES in general has a benign course, PRES-related intracranial hemorrhage has been associated with a poor prognosis. We report a case of variant type of PRES associated with deep brain hemorrhage and discuss the characteristics of PRES-related intracranial hemorrhage via a literature review. A woman aged 41 years with a history of untreated hypertension presented to our hospital complaining of severe headache and with an elevated blood pressure of 237/142 mmHg. Computed tomography revealed a hemorrhage in the left thalamus and basal ganglia. Magnetic resonance imaging revealed remarkable hyperintensity in the left cerebellum, pons, bilateral temporal lobes, bilateral basal ganglia, and bilateral cerebral white matter on fluid-attenuated inversion recovery imaging, which represented vasogenic edema. The parieto-occipital regions were unremarkable. Given this clinical presentation, PRES associated with deep brain hemorrhage was suspected. The patient received strict blood pressure control treatment, which resulted in gradual symptom improvement. Magnetic resonance images obtained 1 month after admission demonstrated an almost complete resolution of the edema. Although hemorrhage in the thalamus, basal ganglia, or brainstem is uncommon in patients with PRES, it may occur in patients with variant type of PRES involving these lesions. It is important to recognize the presence of variant patterns of clinical features and radiologic findings of PRES to allow for early identification and appropriate treatment.